Replaces V1 Primitives in README.md with V2 Primitives. (backport #13487)

[mergify]

Summary

This PR replaces V1 Primitives in README.md with V2 Primitives.

Fixes #12824 (comment)

Details and comments

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This is an automatic backport of pull request #13487 done by [Mergify](https://mergify.com).

[qiskit-bot]

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[coveralls]

Pull Request Test Coverage Report for Build 12015252156

Details

• 0 of 0 changed or added relevant lines in 0 files are covered.
• 4 unchanged lines in 2 files lost coverage.
• Overall coverage decreased (-0.7%) to 88.215%

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Files with Coverage Reduction	New Missed Lines	%
crates/accelerate/src/unitary_synthesis.rs	1	92.2%
crates/qasm2/src/lex.rs	3	91.98%

Totals
Change from base Build 11979134376:	-0.7%
Covered Lines:	50302
Relevant Lines:	57022

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💛 - Coveralls